Hernia repair is a relatively straightforward surgical procedure, the ultimate goal of which is to restore the mechanical integrity of the abdominal wall by repairing a muscle wall defect through which the peritoneum and possibly a section of the underlying viscera has protruded. There are various types of hernias, each with its own specific surgical repair procedure, including ventral hernias, umbilical hernias, incisional hernias, sports hernias, femoral hernias, and inguinal hernias. It is believed that most hernias are attributable to a weakness in sections of the tissues of the abdominal wall.
Precipitating events, such as unusual movements or lifting extremely heavy weights, may cause the weak spots in the abdominal wall tissue to be excessively stressed, resulting in tissue separation or rupture and protrusion of a section of peritoneum and underlying viscera, e.g., intestine, through the separated or ruptured tissue section. This weakness may be attributable to several factors. Weakness in the abdominal wall may be congenital or may be associated with a prior incision from a surgical procedure or a trocar wound. Other factors may include trauma, genetic predisposition, and aging.
Even though the commonly used, conventional surgical procedures for correcting or repairing the various types of hernias are somewhat specific, there is a commonality with respect to the mechanical repair. Typically, the protrusion of the peritoneum through a muscle or abdominal wall defect results in a hernia sack containing the underlying and protruding viscera. The hernia sack is dissected and the viscera are pushed back into the abdominal cavity. Then, a tissue reinforcing or repair implant such a mesh patch device is typically implanted and secured at the site of the abdominal wall defect. Autologous tissue quickly grows into the mesh implant, providing the patient with a secure and strong repair. In certain patient presentations, it may be desirable to suture or otherwise close the defect without an implant, although this is typically much less desirable for the optimal outcome.
One common type of hernia is a ventral hernia. This type of hernia typically occurs in the abdominal wall and may be caused by a prior incision or puncture, or by an area of tissue weakness that is stressed. There are several repair procedures that can be employed by the surgeon to treat such hernias, depending upon the individual characteristics of the patient and the nature of the hernia. In one technique, an onlay mesh is implanted on the dorsal surface of the anterior fascia of the abdominal wall. Another technique provides for an inlay mesh, where the prosthetic material is sutured to the abdominal wall and acts as a “bridge” to close the abdominal defect. Placement of a prosthetic mesh posterior to the rectus muscle of the abdominal wall is known as the Reeves Stoppa or retromuscular technique. In this technique, a mesh implant is located beneath the muscle of the abdominal wall but above the peritoneum. Implantation of the mesh in the intra-peritoneal location can be done via an open or laparoscopic approach. The mesh is inserted into the patient's abdominal cavity through an open anterior incision or via a trocar and positioned to cover the defect. The surgeon then fixates the mesh implant to the abdominal wall with conventional mechanical fixation or with sutures placed through the full thickness of the abdominal wall. There are a variety of such mechanical fixation devices that can be used in laparoscopic or open surgery, e.g., tacking instruments. Intraperitoneal placement of mesh via an open approach may be the desired technique of repair where the layers of the abdominal wall are attenuated and a laparoscopic approach is not desired. Placement of mesh via this technique presents several unique challenges including poor visibility during mesh handling and fixation, poor handling, and deficient ergonomics of the currently available products. Mesh repair patch implants designed for intraperitoneal placement typically requires an additional treatment or layer to function as a tissue separating component to separate the viscera from the prosthetic abdominal wall repair layer, and thereby prevent or substantially inhibit the formation of post-operative adhesions. The addition of this layer may add to the complexity of wound healing due to the presence and mass of an additional layer.
Although hernia repair patch implants exist for open ventral hernia repairs, there are deficiencies known to be associated with their use. The deficiencies include difficulty in handling the mesh, poor visibility during mesh handling, implantation and fixation, poor usability and ergonomics when using a laparoscopic instrument, and the use of dual or multiple layers of mesh. The commercially available meshes repair patch implants for this application typically have at least dual layers of mesh or fabric with pockets or skirts to provide for affixation to the parietal wall via the top layer or skirt. It can also be appreciated that multiple layer meshes introduce more foreign body mass and tend to be more expensive and complicated to manufacture than a single layer mesh implant. Another deficiency associated with hernia repair patch implants is the ease of locating the periphery of the patches so that a surgeon may affix the patch to tissue by emplacing tacks or other fasteners to properly secure the implants to tissue in the appropriate manner.
Accordingly, there is a need in this art for novel tissue repair implants, such as ventral hernia repair patch implants, that can be used in an open surgical procedure, and which do not require a mesh anchoring or affixation layer, and which may be secured to tissue using a single or multiple crown technique. There is also a need for tissue repair implants which facilitate the location of the peripheries of such implants by the surgeon.